Methods and Systems for Fastening Components

ABSTRACT

Bed foundation beams are sandwiched by a compression bar extending parallel to the first and second rails and moved towards the first and second rails while being conveyed. Further, the first and second rails and the spacers are sandwiched against spaced fixtures on an endless chain. While being compressed and sandwiched, staple guns fasten the rails and spacers together. The fixtures include front and back stops, with the back stop pivotable about a fixture axis to be movable by a cam moving in a cam track from a pushing position extending perpendicular to the endless chain and abutting with a trailing edge of one of the spacers and a non-intervening position after the staple gun and before the sprocket of the endless chain to reduce the apparatus footprint.

BACKGROUND

Apparatus and methods for fastening components such as beams for bedfoundations are shown and described.

In the fabrication of bed foundations, it is necessary to fabricate sideand center beams B by fastening spacers S between first and second railsR and an end stop E. Conventionally, after spacers S are fed frommagazines M, an operator places rails R and end stop E on opposite sidesthereof, and the unassembled rails R, end stop E and spacers S areconveyed in a direction parallel to the rails R and end stop E paststaple guns G which drive staples through rails R and into spacers S andthrough end stop E and into first rail R. To reduce the spacing betweenthe rails R, end stop E and spacers S, conventionally, the unassembledrails R, end stop E and spacers S were compressed together by funnelingsurfaces as the unassembled rails R, end stop E and spacers S were beingconveyed. However, this resulted in several operational disadvantagesincluding, but not limited to, jamming of the unassembled rails R, endstop E and spacers S when being conveyed, which required operatorattention to unjam, and inconsistent fastening of the rails R, end stopE and spacers S. Further, the conveying mechanism was required to extendbeyond the staple guns G for the complete length of the rails R, makingthe foot print of the apparatus significant.

Thus, there is a need for apparatus and methods for fasteningcomponents, such as rails and spacers, which overcome the operationaldisadvantages and reduce the required foot print.

SUMMARY

This need and other problems in the field of component fastening issolved by providing novel apparatus and methods for fasteningcomponents. A compression bar extends parallel to first and second railsreceived in spaced fixtures and being conveyed by a conveyor in aconveying direction to compress the first and second rails againstspacers. Also, the first and second rails and the spacers are sandwichedagainst the spaced fixtures. Thus, jamming of the first and second railsand the spacers being conveyed to a gun for driving fasteners into thefirst and second rails and the spacers is avoided. In an aspect, thecompression bar is moved by air cylinders connected between first andsecond arms extending perpendicularly from the compression bar and theapparatus frame. In another aspect, multiple claws having an extendedshape perpendicular to their pivot axes are biased by air springs toabut with the first and second rails and the spacers while beingconveyed.

Further, the fixtures include front and back stops which abut withleading and trailing portions of the first and second rails and thespacers while being conveyed in the conveying direction. The back stopis pivotable about a fixture axis and is movable between a pushingposition extending generally perpendicular to the conveying directionand a non-intervening position extending at an acute angle to theendless chain of the conveyor. While components are being conveyed to agun for driving fasteners into the components, the front stop abuts withthe leading portion of the components, and the back stop is in thepushing position and abuts with the trailing portion of the components.After fastening and before the fixture reaches the sprocket of theendless chain, the back stop is pivoted to its non-intervening positionto reduce the apparatus footprint. In an aspect, the back stop ispivoted by a cam fixed to an axle of the back stop which engages with acam track extending parallel to the conveyor. In some aspects, the backstops of the fixtures abut with the trailing edges of the spacers. Thefront stop of one fixture is forwardly arcuately shaped to abut with theleading portion of the first and second rails and the spacers while theopposite ends of the first and second rails and the spacers abuts with arearwardly arcuately shaped back stop of another, spaced fixture.

Illustrative embodiments will become clearer in light of the followingdetailed description in connection with the drawings.

DESCRIPTION OF THE DRAWINGS

The illustrative embodiments may best be described by reference to theaccompanying drawings where:

FIG. 1 shows a perspective view of an apparatus for fastening beams forbed foundations, with portions broken away and removed.

FIG. 2 shows a perspective view of a beam for bed foundations.

FIG. 3 shows a perspective view of the conveying mechanism of theapparatus of FIG. 1 with portions broken away and removed.

FIGS. 4-7 show perspective views of fixture elements of the apparatus ofFIG. 1.

FIGS. 8 and 9 show perspective views of the compressing assembly ofapparatus of FIG. 1 with portions broken away and removed.

FIGS. 10 and 11 show partial side views of the apparatus of FIG. 1 withportions broken away and removed.

FIG. 12 shows a perspective view of a conveying mechanism of analternate apparatus for fastening beams for bed foundations, withportions broken away and removed.

FIGS. 13 and 14 show perpective views of fixture elements of theapparatus of FIG. 12.

FIGS. 15 and 16 show perspective views of the compressing assembly ofthe apparatus of FIG. 12.

All figures are drawn for ease of explanation of the basic teachingsonly; the extensions of the figures with respect to number, position,relationship, and dimensions of the parts to form the illustrativeembodiments will be explained or will be within the skill of the artafter the following description has been read and understood. Further,the exact dimensions and dimensional proportions to conform to specificforce, weight, strength, and similar requirements will likewise bewithin the skill of the art after the following description has beenread and understood.

Where used in the various figures of the drawings, the same numeralsdesignate the same or similar parts. Furthermore, when the terms “top”,“bottom”, “first”, “second”, “forward”, “rearward”, “reverse”, “front”,“back”, “height”, “width”, “length”, “end”, “side”, “horizontal”,“vertical”, and similar terms are used herein, it should be understoodthat these terms have reference only to the structure shown in thedrawings as it would appear to a person viewing the drawings and areutilized only to facilitate describing the illustrative embodiments.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

An apparatus for fastening components and particularly beams for bedfoundations is shown and generally designated 10. Apparatus 10 generallyincludes a conveyor or conveying mechanism for conveying components in aconveying movement direction shown as an endless chain 12 extendingaround a sprocket 14 located before the magazines M in the conveyingdirection and a sprocket 16 located after the staple guns G in theconveying direction. In the form shown, endless chain 12 is formed of asingle series of roller links L with some of the links L including tabsT extending in opposite directions from link L perpendicular to theconveying direction.

Conveying mechanism further includes fixtures F1, F2 and F3 attachableto tabs T of endless chain 12 and spaced in the conveying direction. Itshould be appreciated that fixtures F1, F2 and F3 can be attached tocorresponding tabs T according to the particular length of rails R andspacing between spacers S of the particular bed foundation desired. Inparticular, fixtures F1 and F2 include a hinge mount 20 which can beremovably attached to tabs T such as by fasteners 22. Hinge mount 20includes an axle 24 rotatably mounted thereto about a fixture axisperpendicular to the conveying direction. A back stop shown as a pushtab 26 is secured to axle 24 for pivotable movement relative to endlesschain 12 between a pushing position extending generally perpendicular tohinge mount 20, to endless chain 12 and to the conveying direction and anon-interfering position. A cam 28 is secured to axle 24 outwardly ofhinge mount 20 and push tab 26 and extends generally perpendicularly toaxle 24 and push tab 26.

Fixtures F1 and F2 include a chain mount 30 which can be attached totabs T such as by fasteners 22. Fixture F1 includes a front stop 32extending generally arcuately from the chain mount 30 forwardly in theconveying direction and upwardly away from the endless chain 12 andconfigured to accept the arcuate shaped ends of rails R. Front stops 32includes openings 34 formed therein. Fixture F2 includes a front stop 36extending generally perpendicular from chain mount 30 and endless chain12 to the front of chain mount 30 in the conveying direction. Push tabs26 are spaced from front stops 32 and 36 in the conveying direction andare pivotable relative to endless chain 12 away from front stops 32 and36. Fixture F3 includes a chain mount 40 which can be attached to tabs Tsuch as by fasteners 22, and can include an arch 42 of a size to receiveendless chain 12 when traveling around sprockets 14 and 16. Fixture F3further includes first and second back stops 44 removably secured tochain mount 40 and extending generally arcuately from chain mount 40rearwardly in the conveying direction and upwardly away from the endlesschain 12 and configured to accept the arcuate shaped ends of rails R.Legs 46 integrally extend perpendicularly from the front edge of chainmount 40 in the conveying direction and away from the endless chain 12.Adjustable bolts 48 are threadably received in legs 46 and extendparallel to the chain mount 40 and the endless chain 12.

It should then be appreciated that rails R can be placed in theconveying mechanism between fixtures F1 and F3 parallel to the conveyingdirection with the leading portion or ends of rails R received in frontstop 32 and the trailing portion or ends of rails R received in backstops 44. Further, the leading edges or sides of spacers S abut withfront stops 36 of fixtures F2 and F3, and the trailing edges or sides ofspacers S abut with push tabs 26 in the pushing position.

Apparatus 10 further includes compressing assemblies for compressingrails R and spacers S together before fastening. In the form shown, acompression bar 50 extends parallel to the endless chain 12 and theconveying direction and is horizontally movable toward and away from theendless chain 12 generally perpendicular to the conveying direction. Inthe form shown, first and second arms 52 extend generally perpendicularto compression bar 50 and are suitably slidably supported to a frame ofapparatus 10 such as by slides 52A mounted to apparatus 10. Compressionbar 50 is movable perpendicular to the conveying direction between aloading position and a compressed position located closer to the endlesschain 12 such as by air cylinders 54 having one end connected to arms 52and an opposite end connected to the frame of the apparatus 10. Inoperation, compression bar 50 is located in its loading position andendless chain 12 is positioned with fixtures F2 aligned with magazinesM. Spacers S are fed from the magazines M, and rails R are placedbetween fixtures F1 and F3 by the operator. After placement, compressionbar 50 can be moved from its loading position to its compressed positionto compress and sandwich rails R against spacers S by retracting aircylinders 54. After and while being compressed, endless chain 12 can beadvanced to move the compressed rails R and spacers S toward the stapleguns G.

In the form shown, hold downs H are positioned above the endless chain12 for holding down the rails R and spacers S before entering the stapleguns G. Particularly, hold down H can be of a variety of configurationsbut each include generally a clamp 60 for fixing to the frame ofapparatus 10 and include parallel pivot plates 62 secured thereto. Atleast one claw 64 is pivotably mounted about a pivot axis extendingperpendicular to the conveying direction between the pivot plates 62 andis of an extended shape and particularly of a J-shape perpendicular tothe pivot axis. Claw 64 extends at a large acute angle in the order of60° to the conveying direction and includes its upper end pivotablymounted between pivot plates 62 and its lower end extending in theconveying direction. An air spring 66 biases the claw 64 to pivot aboutthe pivot axis in the conveying direction and towards the endless chain12 and includes a first end connected to pivot plates 62 and a secondend connected to claw 64. The width of claws 64 corresponds to thethickness of rails R and spacers S which they engage, with the width ofclaw 64 which engages spacers S shown as being perpendicular to thethickness of the claw 64 and as being a whole number multiple of widthsof claws 64 which engage rails R, whereas the width of claws 64 whichengage rails R being the thickness of the claw 64. Thus, as endlesschain 12 advances moving the fixtures F1, F2 and F3 and the compressedrails R and spacers S toward the fastening location of staple guns G,rails R and spacers S will push and pivot hold downs H against the biasof the air springs 66, with the second ends of the claws 64 pushingagainst and sandwiching the rails R and spacers S downward against thefixtures F1, F2 and F3 as the endless chain 12 advances. While beingsandwiched, staple gun G drives fasteners, such as staples, to fastenrails R and spacers S together.

Apparatus 10 further includes a cam track 70 extending parallel to andspaced from the endless chain 12 for engagement by cam 28. Specifically,when cam track 28 engages cam track 70, push tab 26 is held in itspushing position. Cam track 70 terminates before the sprocket 16 in theconveying direction to allow the push tab 26 to move from its pushingposition to a non-intervening position with the spacer S after rails Rand spacers S are fastened by staple gun G and before reaching sprocket16. Thus, it is possible for the endless chain 12 to follow sprocket 16since fixtures F1 and F2 do not have to follow spacers S. Thus, thedistance between sprockets 14 and 16 can be reduced to reduce thefootprint of the apparatus 10. Suitable provisions can ensure that cam28 will engage with cam track 70 after fixtures F1 and F2 are below theupper run of the endless chain 12 such as by a pivot trip cog 76 whichengages with cams 28 and is biased to its engagement position such as byan air spring 78.

In an alternate form, an apparatus for fastening components andparticularly beams for bed foundations is shown and generally designated10 a. Apparatus 10 a generally includes a conveyor or conveyingmechanism for conveying components in a conveying movement directionshown as an endless chain 12 extending around sprockets 14 and 16.Conveying mechanism further includes fixtures F1 a, F2 a and F3 aattachable to endless chain 12 and spaced in the conveying direction.Fixtures F1 a and F2 a include a chain mount 30 a which can be attachedto tabs T such as by fasteners 22. Chain mount 30 a includes a step 30 blocated intermediate and spaced from the side edges thereof. Fixture F1a includes a front stop 32 a extending generally arcuately from thechain mount 30 a forwardly in the conveying direction and upwardly awayfrom the endless chain 12 and configured to accept the arcuate shapedends of rails R. Fixture F2 a includes a front stop 36 extendinggenerally perpendicular from chain mount 30 a and endless chain 12 tothe front of chain mount 30 a in the conveying direction.

Apparatus 10 a further includes hold downs Ha and Hb positioned abovethe endless chain 12 for holding down the rails R, end stop E andspacers S before entering the staple guns G. Particularly, hold down Hacan be of a variety of configurations but each include generally a clamp60 a for fixing to the frame of apparatus 10 a and include parallelpivot plates 62 a secured thereto. Pivot plates 62 a are generallyC-shaped and are sandwiched together with inner notches formed on theends thereof. A claw 64 a is pivotably mounted about a pivot axisextending perpendicular to the conveying direction between the pivotplates 62 a and is of an extended shape and particularly of a J-shapeperpendicular to the pivot axis. Claw 64 extends at a small acute anglein the order of 15° to the conveying direction and includes its forward,upper end pivotably mounted between pivot plates 62 a and its rearward,lower end extending in the conveying direction. An air spring 66 abiases the claw 64 a to pivot about the pivot axis in the conveyingdirection and towards the endless chain 62 and includes a first endpivotably connected to pivot plates 62 a and a second end connected toclaw 64 a. The width of claws 64 a corresponds to the thickness of railsR and end stop E which they engage. Additionally, hold down Hb can be ofa variety of configurations but includes generally a clamp 60 b forfixing to the frame of apparatus 10 b and includes spaced, parallelpivot plates 62 b secured thereto. A claw 64 b is pivotably mountedabout a pivot axis extending perpendicular to the conveying directionbetween the pivot plates 62 b and is of an elongated shape andparticularly of a ski-shape perpendicular to the pivot axis. The tipportion of claw 64 b extends at a small acute angle in the order of 15°to the conveying direction, and the trailing portion of claw 64 bextends generally parallel to the conveying direction. Claw 64 bincludes its forward, upper end pivotably mounted between pivot plates62 b and its rear, lower end extending in the conveying direction. Anair spring 66 b biases the claw 64 b to pivot about the pivot axis inthe conveying direction and towards the endless chain 62 and includes afirst end pivotably connected to pivot plates 62 b and a second endconnected to claw 64 b. The width of claw 64 b corresponds to thethickness of spacers S which it engages, with the width of claw 64 bwhich engages spacers S shown as being perpendicular to the thickness ofthe claw 64 b and as being a whole number multiple of widths of claws 64a which engage rails R and end stop E, whereas the width of claws 64 awhich engage rails R and end stop E being the thickness of the claw 64a. Thus, as endless chain 12 advances moving the fixtures F1 a, F2 andF3 a and the compressed rails R, end stop E and spacers S toward thefastening location of staple guns G, rails R, end stop E and spacers Swill push and pivot hold downs Ha and Hb against the bias of the airsprings 66 a and 66 b, with the second ends of the, claws 64 a and 64 bpushing against and sandwiching the rails R, end stop E and spacers Sdownward against the fixtures F1 a, F2 and F3 a as the endless chain 12advances.

Thus, since the invention disclosed herein may be embodied in otherspecific forms without departing from the spirit or generalcharacteristics thereof, some of which forms have been indicated, theembodiments described herein are to be considered in all respectsillustrative and not restrictive. The scope of the invention is to beindicated by the appended claims, rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims are intended to be embraced therein.

1. Method comprising: providing a conveyor moving in a conveyingdirection and including spaced fixtures; placing first and second railsparallel to the conveying direction and between the spaced fixtures andspacers perpendicular to the conveying direction and between the firstand second rails; moving a compression bar extending parallel to theconveying direction from a loading position to a compressing positioncompressing the first and second rails against the spacers; while beingcompressed, conveying the first and second rails and the spacers in theconveying direction; while being conveyed, sandwiching the first andsecond rails and the spacers against the spaced fixtures; and whilebeing sandwiched, fastening the first and second rails and the spacerstogether.
 2. The method of claim 1, wherein moving comprises slidablymounting first and second arms extending perpendicular to thecompression bar in a frame upon which the conveyor is provided, andmoving the first and second arms perpendicular to the conveyingdirection; and wherein moving the first and second arms comprisesproviding air cylinders connected between the first and second arms andthe frame, and retracting the air cylinders.
 3. The method of claim 1,wherein sandwiching comprises pivotably mounting at least one claw abouta pivot axis extending perpendicular to the conveying direction, withthe at least one claw having an extended shape perpendicular to thepivot axis; biasing the at least one claw to pivot about the pivot axisin the conveying direction; and abutting an end of the at least one clawopposite to the pivot axis with at least one of the first and secondrails and the spacers while being conveyed.
 4. The method of claim 3,wherein pivotably mounting comprises pivotably mounting first, second,third and fourth claws, with the ends of the first and second clawsabutting with the first rail, with the third claw abutting with thespacers, with the fourth claw abutting with the second rail, with thethird rail having a width parallel to the pivot axis which is a wholenumber multiple of widths parallel to the pivot axis of the first,second and fourth claws.
 5. The method of claim 4, wherein providingcomprises providing the conveyor including an endless chain moving inthe conveying direction to extend around a sprocket, with the spacedfixtures including a first fixture on the endless chain, with the firstfixture including a front stop and a back stop spaced from the frontstop in the conveying direction and pivotable about a fixture axisrelative to the endless chain away from the front stop, wherein placingcomprises abutting a leading portion of the first and second rails andthe spacers with the front stop and abutting a trailing portion of thefirst and second rails and the spacers with the back stop extendingperpendicular to the endless chain and the conveying direction, andwherein the method further comprises: after fastening, moving the firstfixture in the conveying direction towards the sprocket; and pivotingthe back stop of the first fixture when moving in the conveyingdirection and before reaching the sprocket to an acute angle to theendless chain.
 6. Apparatus for fastening spacers between first andsecond rails, comprising, in combination: a conveyor movable in aconveying direction and including spaced fixtures adapted to receive thefirst and second rails extending in the conveying direction; acompression bar extending parallel to the conveyor and the conveyingdirection and movable perpendicular to the conveying direction from aloading position to a compressing position, with the compression barbeing closer to the conveyor in the compressing position than in theloading position; at least one claw pivotably mounted about a pivot axisextending perpendicular to the conveying direction, with the at leastone claw having an extended shape perpendicular to the pivot axis, withthe at least one claw biased to pivot about the pivot axis opposite tothe conveying direction, with the at least one claw having an endopposite to the pivot axis adapted to abut at least one of the first andsecond rails and the spacers while being conveyed in the conveyingdirection by the conveyor; and a gun adapted to drive fasteners into atleast one of the first and second rails and at least one of the spacers.7. The apparatus of claim 6 further comprising, in combination: firstand second arms extending generally perpendicular to the compressionbar, wherein the conveyor is movable relative to a frame; slides mountedto the frame slidably mounting the first and second arms for movementperpendicular to the conveying direction; and an air cylinder extendingbetween the frame and one of the first and second arms, with the aircylinder being expandable and retractable to move the one of the firstand second arms relative to the frame.
 8. The apparatus of claim 7,wherein the at least one claw comprises first, second third and fourthclaws, with the ends of the first and second claws adapted to abut withthe first rail, with the end of the third claw adapted to abut with thespacers, with the end of the fourth claw adapted to abut with the secondrail, with the third rail having a width parallel to the pivot axiswhich is a whole number multiple of widths parallel to the pivot axis ofthe first, second and fourth claws; and wherein the apparatus furthercomprises, in combination: an air spring extending between the frame andthe at least one claw and biasing the at least one claw to pivot aboutthe pivot axis in the conveying direction.
 9. The apparatus of claim 8,wherein the conveyor includes an endless chain moving in the conveyingdirection to extend around a sprocket, with the spaced fixturesincluding a first fixture on the endless chain, with the first fixtureincluding a front stop and a back stop spaced from the front stop in theconveying direction and pivotable about a fixture axis relative to theendless chain away from the front stop, with the front stop adapted toabut a leading portion of the first and second rails and the spacers,with the back stop extending perpendicular to the endless chain and theconveying direction and adapted to abut with a trailing portion of thefirst and second rails and the spacers, with the back stop pivotable toan acute angle relative to the endless chain intermediate the gun andthe sprocket.
 10. Method comprising: providing a first fixture on anendless chain moving in a conveying direction to extend around asprocket, with the first fixture including a front stop and a back stopspaced from the front stop in the conveying direction and pivotableabout a fixture axis relative to the endless chain away from the frontstop; placing components to be fastened in the first fixture with aleading portion of the components abutting with the front stop and witha trailing portion of the components abutting with the back stopextending perpendicular to the endless chain and the conveyingdirection; moving the first fixture and the endless chain with the backstop extending perpendicular to the endless chain to a fasteninglocation; fastening the components together at the fastening location;after fastening, moving the first fixture in the conveying directiontowards the sprocket; and pivoting the back stop of the first fixturewhen moving in the conveying direction and before reaching the sprocketto an acute angle to the endless chain.
 11. The method of claim 10,wherein placing comprises placing first and second rails parallel to theconveying direction and spacers perpendicular to the conveying directionbetween the first and second rails in the first fixture with thetrailing portion of one of the spacers abutting with the back stop. 12.The method of claim 11, wherein placing comprises abutting the leadingportion of the one of the spacers with the front stop.
 13. The method ofclaim 11, wherein placing comprises abutting the leading portion of thefirst and second rails with the front stop, and wherein the methodfurther comprises providing a second fixture on the endless chain spacedin the conveying direction for a spacing generally equal to and forreceiving the first and second rails between the first and secondfixtures, and wherein placing includes placing the first and secondrails between the first and second fixtures with ends of the first andsecond rails opposite to the first fixture abutting with the secondfixture.
 14. The method of claim 13, further comprising placing a thirdfixture on the endless chain intermediate the first and second fixturesin the conveying direction, with the third fixture including a frontstop and a back stop spaced from the front stop in the conveyingdirection and pivotable about a fixture axis relative to the endlesschain away from the front stop, and wherein placing comprises placingone of the spacers in the third fixture with a leading edge of the oneof the spacers abutting with the front stop and a trailing edge of theone of the spacers abutting with the back stop of the third fixtureextending perpendicular to the endless chain in the conveying direction.15. Apparatus for fastening components comprising, in combination: anendless chain movable in a conveying direction to extend around asprocket; a first fixture secured to the endless chain, with the firstfixture including a front stop and a back stop spaced from the frontstop in the conveying direction and pivotable about a fixture axisrelative to the endless chain away from the front stop, with the frontstop adapted to abut with a leading portion of the components and withthe back stop extending perpendicular to the endless chain and theconveying direction and adapted to abut with a trailing portion of thecomponents; and a gun adapted to drive fasteners into the components,with the back stop pivotable to an acute angle relative to the endlesschain intermediate the gun and the sprocket.
 16. The apparatus of claim15 further comprising, in combination: a cam track extending parallel toand spaced from the endless chain, wherein the first fixture includes anaxle fixed to the backstop and defining the fixture axis and a camsecured to the axle and extending generally perpendicular to the fixtureaxis, with the cam engaging the cam track and pivoting the back stoprelative to the endless chain.
 17. The apparatus of claim 16, whereinthe endless chain includes a tab, wherein the first fixture comprises ahinge mount including the axle, with the hinge mount removably attachedto the tab; and a chain mount including the front stop, with the chainmount separately formed from the hinge mount and removably attached tothe tab.
 18. The apparatus of claim 17, wherein the components comprisesfirst and second rails extending parallel to the conveying direction andspacers perpendicular to the conveying direction and between the firstand second rails, with one of the spacers including the leading andtrailing portions, wherein the front stop comprises a tab integrallyformed with the chain mount and extending perpendicular to the endlesschain and the conveying direction and parallel to the back stopextending perpendicular to the endless chain and the conveyingdirection.
 19. The apparatus of claim 17, wherein the componentscomprises first and second rails extending parallel to the conveyingdirection and spacers perpendicular to the conveying direction andbetween the first and second rails, with one of the spacers includingthe trailing portion, with the first and second rails including theleading portion, wherein the front stop extends generally arcuately fromthe chain mount forwardly in the conveying direction and upwardly awayfrom the chain mount and the endless chain, with the front stopconfigured to abut with the leading portion of the first and secondrails; wherein the apparatus further comprises a second fixture on theendless chain spaced in the conveying direction for a spacing, with thesecond fixture including an abutment stop extending arcuately rearwardlyin the conveying direction and upwardly away from the endless chain,first and second legs extending perpendicularly to and away from theendless chain, and adjustable bolts threadedly received in the legs andextending parallel to the endless chain, with the front and abutmentstops adapted to accept opposite ends of the first and second rails. 20.The apparatus of claim 19, further comprising, in combination a thirdfixture including a front stop and a back stop spaced from the frontstop in the conveying direction and pivotable about a fixture axisrelative to the endless chain away from the front stop, with the frontstop of the third fixture adapted to abut a leading edge of one of thespacers, with the back stop of the third fixture extending perpendicularto the endless chain and the conveying direction and adapted to abutwith a trailing edge of the one of the spacers.